Aoibhell ruled a sidhe in North Munster, but little is known about
her before she became deminatured into "fairy" status by popular
folklore. Aoibhell means "beautiful" and is taken from the Irish word aoibhinn.
She became the guardian spirit of the Dál g Cais, otherwise known as
the Dalcassians or O'Brien clan. Her home was at the Craig Liath, or
gray rock, which was located two miles north of Killaloe. She was also
the lover of Dubhlainn Ua Artigan. Aoibhell possessed a magic harp
that she gifted to Meardha and it was believed that whoever heard the
harp’s music would not live long afterward.
Resource
Ellis, Peter Berresford. A Dictionary of Irish Mythology. (Santa Barbara,
California: ABC-CLIO, Inc., 1987). Pages 24.